This Lee Large Series Collet Die sizes only the neck to preserve the perfect fit of fire forming. A collet squeezes the case neck against a precision mandrel for a perfect bullet fit with minimum run-out. No case lube is needed. Cases last about 10 times longer. Only reload cases that have been fired in you firearm. Not recommended for autoloaders, slide or lever action guns. Beefed up 1-1/4" x 12 tpi threads will work with the Lee Classic Cast Press. These dies feature the same quality and value that Lee die sets are known for, just in a larger version.
Notes: Collet neck sizer uses a collet to squeeze the case neck against a mandrel, creating a precisely aligned case neck while reducing runout.